Brand name:
Antiosteoporotic Products
One-Alpha (Alfacalcidol, AlfaD)
Composition
ALFACIP (Alfacalcidol, One-Alpha. AlfaD) 0.25 micro gm
Each soft gelatin capsule contains alfacalcidol (1-alpha hydroxyvitamin
D 3 ) 0.25mcg (green capsule)
Description One-Alpha (Alfacalcidol, AlfaD)
Alfacalcidol (1-alpha hydroxy) undergoes rapid hepatic conversion
to 1,25 – dihydroxyvitamin D 3 the vitamin D 3 metabolite which
acts as a regulator of calcium and phosphate metabolism. The main effects
are to increase circulating 1, 25 dihydroxyvitamin D 3 levels,
and thereby to increase intestinal absorption of calcium and phosphate,
promote bone mineralisation, decrease plasma parathyroid hormone levels
as well as to decrease bone resorption, with relief of bone and muscle
pain. Treatment of intestinal calcium malabsorption associated with
post-menopausal, senile and steroid-induced osteoporosis, with ALFACIP (Alfacalcidol, One-Alpha. AlfaD)
improves the negative calcium balance of these patients. The more positive
calcium balance produced by alfacalcidol treatment in the osteoporotic
patients, decreases bone loss and bone fracture rate.
Indications
ALFACIP (Alfacalcidol, One-Alpha. AlfaD) is used for treating conditions in which calcium metabolism
is disturbed due to impaired 1-alpha hydroxylation, such as reduced
renal function; in other disorders associated with Vitamin D resistance;
and in calcium malabsorption of osteoporosis.
The main indications are:
•
Renal bone disease (renal osteodystrophy)
•
Hypoparathyroidism
•
Hypoparathyroidism (with bone disease)
•
Nutritional and malabsorptive rickets and osteomalacia
•
Hypophosphataemic Vitamin D-resistant rickets and osteomalacia
•
Pseudo-deficiency (D-dependent Type I) rickets with osteomalacia
•
Osteoporosis
Dosage And Administration
General
The dosage and administration of ALFACIP (Alfacalcidol, One-Alpha. AlfaD) should be adjusted according
to the indication-specific notes as follows:
The initial dose is
All indications, excepting osteoporosis:
Adults
1 mcg/day
Elderly patients
0.5 mcg /day
Children
20 kg and over
Excepting in renal osteodystrophy 1 mcg/day
In renal osteodystrophy
0.04-0.08 mcg /kg/day
Children under 20 kg
0.05 mcg /kg/day
Osteoporosis
0.5 mcg/day
The dose should subsequently be adjusted to avoid hypercalcaemia,
according to the biochemical response. Plasma calcium levels (preferably
corrected for protein binding) should initially be measured weekly.
The dose of ALFACIP (Alfacalcidol, One-Alpha. AlfaD) can be increased by increments of 0.25 to 0.5 m
cg /day. Most adults respond to doses of 1 to 3 mcg /day. Once the
dose is stabilised, calcium levels should be measured periodically.
Children with renal osteodystrophy seem to need relatively higher doses
than adults and may even need the adult dose.
Contraindications One-Alpha (Alfacalcidol, AlfaD)
ALFACIP (Alfacalcidol, One-Alpha. AlfaD) should not be administered in the presence of hypercalcaemia,
hyperphosphataemia (except when occurring with hypoparathyroidism)
or hypermagnesaemia. ALFACIP (Alfacalcidol, One-Alpha. AlfaD) should not be used in patients with evidence
of Vitamin D toxicity or known hypersensitivity to the effects of Vitamin
D or any of its analogues.
Warnings and Precautions
Alfacalcidol increases the intestinal absorption of calcium and phosphate,
serum levels of which should be monitored, particularly in patients
with renal failure. Throughout treatment with Alfacalcidol regular
plasma and urinary (24-hour collection) calcium levels should be determined
at least once every three months months. Alfacalcidol therapy requires
regular monitoring of calcium phosphate, alkaline phosphate, magnesium
and creatinine levels as well as other appropriate biochemical parameters
and should only be prescribed when suitable facilities are available.
If there is biochemical evidence of bone healing (eg. return towards
normal serum alkaline phosphate levels), hypercalcaemia may develop
if the dose of Alfacalcidol is not decreased appropriately; if hypercalcaemia
or hypercalcuria occur, this can be corrected rapidly by stopping treatment
with Alfacalcidol and any calcium supplements until plasma calcium
levels return to normal, usually in about a week.
Alfacalcidol should be administered with caution to patients with
hypercalcaemia especially those with a history of renal calculi.
Drug interactions
Alfacalcidol/Digitalis/Glycosides
Hypercalcaemia in patients taking digitalis preparations may precipitate
cardiac arrhythmias. Patients taking digitalis concurrently with alfacalcidol
must therefore be closely monitored. Alfacalcidol/Barbiturates/Enzyme-inducing
Anticonvulsant Drugs
Patients on barbiturates or other enzyme-inducing anticonvulsants may
require an increased dose of alfacalcidol to produce the desired effect.
Alfacalcidol/Drugs affecting intestinal absorption
Absorption of alfacalcidol may be impaired by concurrent use of mineral
oil (prolonged use), cholestyramine, colestipol, sucralfate or large
amounts of aluminium-based antacids.
Alfacalcidol/Magnesium
Caution should be exercised in the use of magnesium-based antacids
or laxatives for patients taking alfacalcidol who are on chronic renal
dialysis. Hypermagnesaemia may occur.
Alfacalcidol/Calcium/Thiazides
The risk of hypercalcaemia is increased in patients taking calcium-containing
preparations or thiazide diuretics concurrently with alfacalcidol.
Alfacalcidol/Vitamin D and Derivatives
Alfacalcidol is a potent derivative of Vitamin D. Pharmacological doses
of vitamin D and its derivatives should not be given during alfacalcidol
treatment because of the possibility of additive effects and an increased
risk of hypercalcaemia.
Pregnancy
There is insufficient evidence on which to assess the safety of alfacalcidol
use during pregnancy. Animal study has not revealed any hazard but
as with all drugs ALFACIP (Alfacalcidol, One-Alpha. AlfaD) should only be used during pregnancy if
treatment is essential and no better alternative is available.
Lactation
Although not definitely established, it is likely that increased levels
of 1,25-dihydroxyvitamin D 3 will be found in the breast milk of mothers
treated with alfacalcidol. This might have some influence on calcium
metabolism in a breast-feeding infant and discontinuation of breast-feeding
should be considered
Side effects One-Alpha (Alfacalcidol, AlfaD)
Adverse effects generally relate to hypercalcaemia and in the case
of renal impairment, hyperphosphataemia which may be induced by alfacalcidol
therapy.
Hypercalcaemia may manifest as malaise, fatigue, weakness, dizziness,
headache, nausea, dry mouth, constipation, diarrhoea, heartburn, vomiting,
abdominal pain or other gastrointestinal discomfort, muscle pain, bone
pain, joint pain, pruritus or palpitations. In hypercalcaemic dialysis
patients, the possibility of calcium influx from the dialysate should
be considered. No other side effects associated directly with alfacalcidol
therapy have been noted
Presentation
